Most times being unintended and undesirable that can result in imprecise processing and deteriorated surface qualities, machining vibration during the machining of any machining center can be the most troubling problem that the machining center tool industry tries to avoid. Vibration can result from a number of conditions, acting alone or in combination, such as inproper configuration in cutting parameters, dynamic unbalance in cutting tool assembly, chattering correspond to the relative movement between the workpiece and the cutting tool that can result in waves on the machined surface, thickness variation in workpiece that is to be machined, and resonance, etc. Since the effect of machining vibration can severe that, for instance, it can accelerate rates of wear in cutting tools, can cause the surface quality of a workpiece to deteriorate, and even cause deterioration in spindle accuracy, it is important for a machining center to be capable of preventing any machining vibration in an automatic manner during machining without inducing any adverse affect upon its machining efficiency.
In a prior art disclosed in U.S. Pat. No. 5,187,669, a vibration suppression technique is revealed, which teaches the use of an accelerometer to measure a vibration status resulting from a machining process so as to be used as base for controlling a gain in a control circuit and thus suppressing the vibration of the machining process. Please refer to FIG. 1, which is a schematic diagram showing a conventional machining center configuration. In FIG. 1, a computer numerical controller 10 mounted in a machining center 1 is coupled respectively to a feeding module 11, a spindle module 12, a spindle override interface 13 and a feedrate override interface 14, in which the spindle module 12 is further comprised of a spindle 120 and an inverter 121, while the feeding module 11 is further comprised of an X-axial motor 110, a Y-axial motor 111, a Z-axial motor 112 as well as their corresponding drivers 113, 114 and 115 that are connected to the computer numerical controller 10. It is noted that the computer numerical controller 10 is used for generating commands for controlling the spindle module 12 and the feeding module according to a numerical control (NC) code 15 received thereby; and the machining center 1 for enabling the same to perform a two-dimensional displacement whereas the carrier module is used for carrying a workpiece to be processed; and the Z-axial motor 112 is acting as a driving component for enabling the spindle module 12 to move in the Z-axial direction. Generally, the NC code 15 received by the computer numerical controller 10 includes process parameters, such as the material of the workpiece to be processed, the moving path of the carrier module and the spindle speed of the spindle in the spindle module, and so on. However, under the performing of a machining process, machining vibrations may occur due to the varying machining conditions or the status variations in the machine parts of the machining center, which can seriously affect the quality of the workpiece to be process as well as the precision of the machining process. Nevertheless, since the causes of such machining vibrations are hard to predict, it is difficult to control the machining vibrations simply by adjusting the NC code.
In view of that, there are a feedrate adjusting button 17 and a speed adjusting button 16 disposed in the machining center 1 of FIG. 1 while enabling the two adjusting buttons 17, 16 to be coupled respectively to the feedrate override interface 14 and the spindle override interface 13, by that an user is capable of adjusting the feedrate and the spindle speed in a real-time and on-line manner. However, although there is a manual adjustment mechanism established on the machining center 1 using the two adjusting buttons 16, 17, the manual adjustment tends to be performed differently with different users as there is no standard for the adjustment and thus different users are going to perform the manual adjustment according to their personal experiment. Therefore, it is in need of an external adjustment control architecture for the machining center without the need to change the structure of the machining center that is able to generate a control command automatically according to a detection result for controlling the adjustment of the machining center and thus effectively preventing any machining vibrations from happening in the operating machining center.